Chatter from IP
Recently I added my first fuel additive (PS- grey bottle) to the current tank I am finishing up. About last week i noticed a chatter coming from either the tensioner pulley or the IP, wasn't sure. I checked out the tensioner and it was not the problem. Its seems I am hearing a chatter from the IP. The only way I found this was by opening the hood and looking at something else while the engine was idling. I can't hear the chatter from the cab, and can barely hear it with the hood closed (if I listen carefully). I have the stock timing chain installed, which I hear phaser gears can cause this chatter. Is my IP failing or is it the FSD, or something else? Anybody have ideas? I have about 153K miles on the engine right now. The IP was replaced under warranty back in probably 1998 or so.
94 GMC 2500 HD
Ext Cab, Long bed
6.5TD, Vin F, 4L80E, 3.73 gears
Pinnacle 4" Exhaust
Heath Diesel Turbomaster
172,000 miles